<?php
// +--------------------------------------------------------------------------+
// | Image_Graph aka GraPHPite                                                |
// +--------------------------------------------------------------------------+
// | Copyright (C) 2003, 2004 Jesper Veggerby Hansen                          |
// | Email         pear.nosey@veggerby.dk                                |
// | Web           http://graphpite.sourceforge.net                           |
// | PEAR          http://pear.php.net/pepr/pepr-proposal-show.php?id=145     |
// +--------------------------------------------------------------------------+
// | This library is free software; you can redistribute it and/or            |
// | modify it under the terms of the GNU Lesser General Public               |
// | License as published by the Free Software Foundation; either             |
// | version 2.1 of the License, or (at your option) any later version.       |
// |                                                                          |
// | This library is distributed in the hope that it will be useful,          |
// | but WITHOUT ANY WARRANTY; without even the implied warranty of           |
// | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU        |
// | Lesser General Public License for more details.                          |
// |                                                                          |
// | You should have received a copy of the GNU Lesser General Public         |
// | License along with this library; if not, write to the Free Software      |
// | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA |
// +--------------------------------------------------------------------------+

/**
 * Image_Graph aka GraPHPite - PEAR PHP OO Graph Rendering Utility.
 * @package marker
 * @copyright Copyright (C) 2003, 2004 Jesper Veggerby Hansen
 * @license http://www.gnu.org/licenses/lgpl.txt GNU Lesser General Public License
 * @author Jesper Veggerby Hansen <pear.nosey@veggerby.dk>
 * @version $Id: Angular.php,v 1.1 2008/01/24 01:35:01 tye Exp $
 */ 

/**
 * Include file Graph/Marker/Pointing.php
 */
require_once(IMAGE_GRAPH_PATH . "/Graph/Marker/Pointing.php");

/**
 * Marker that points "away" from the graph.
 * Use this as a marker for displaying another marker pointing to the original point on
 * the graph - where the "pointer" is calculated as line orthogonal to a line drawn between
 * the points neighbours to both sides (an approximate tangent). This should make an
 * the pointer appear to point "straight" out from the graph. The "head" of the pointer
 * is then another marker of any choice. 
 */
class Image_Graph_Marker_Pointing_Angular extends Image_Graph_Marker_Pointing 
{

    /**
     * The length of the angular marker
     * @var int
     * @access private
     */
    var $_radius;

    /**
     * Image_Graph_AngularPointingMarker [Constructor]
     * @param int $radius The "length" of the pointer 
     * @param Marker $markerEnd The ending marker that represents "the head of the pin"
     */
    function &Image_Graph_Marker_Pointing_Angular($radius, & $markerEnd)
    {
        parent::__construct(0, 0, $markerEnd);
        $this->_radius = $radius;
    }

    /**
     * Draw the marker on the canvas
     * @param int $x The X (horizontal) position (in pixels) of the marker on the canvas 
     * @param int $y The Y (vertical) position (in pixels) of the marker on the canvas 
     * @param array $values The values representing the data the marker "points" to 
     * @access private
     */
    function _drawMarker($x, $y, $values = false)
    {
        if (isset($values['LENGTH'])) {
            $this->_deltaX = - $values['AX'] * $this->_radius / $values['LENGTH'];
            $this->_deltaY = - $values['AY'] * $this->_radius / $values['LENGTH'];
        }
        
        if ((isset($values['NPY'])) and (isset($values['APY'])) and (isset($values['PPY'])) and ($values['NPY'] > $values['APY']) and ($values['PPY'] > $values['APY'])) {
            $this->_deltaX = - $this->_deltaX;
            $this->_deltaY = - $this->_deltaY;
        }
        parent::_drawMarker($x, $y, $values);
    }

}

?>